There are three points I'd make in response to your question, briefly.
Should there be a set price for carbon? The price of carbon you can do two ways: you can set a price for carbon, or create a demand for carbon offsets on the basis of a regulatory regime.
Again, my third point was innovation. Therefore, most businesses and most members of the EXCEL Partnership like the idea of a market-based carbon instrument but understand that you have to drive that to some regulatory basis. I also said there needs to be a short term and a long term. So read into that that we have to make a transition from an initial set of regulations, and over time you're going to strengthen those.
The challenge for business obviously has been in a competitive context: how do you do that across economies, especially with other countries? That's why some aspects of the sectoral targets in the Bali discussions were useful. So we do need a carbon market, and we do need a market to drive carbon offsets. I would suggest that pegging a price is not the most effective way. It's not as innovative as you would get if you created a demand for carbon offsets by having some manner of regulatory regime that changes over time and really recognizes that capital stock investment has to take place.
In terms of the trading regime, and if we don't do this, do we have a barrier to trade relative to other economies that are acting under the protocol, such as in Europe, I don't think so, in the short term. I can't see how it will evolve. But the reality is that businesses would rather have clarity for capital investment, and business is global; therefore, business would rather have us keep pace with a global movement to act, rather than stand back.
So I would say an open market is better, with more innovation, and drive it with the regimes that you create. Just make sure that they recognize competitive realities too.